Currently, in a known information transmission technology, a transmit end device may notify a receive end device of a status (for ease of understanding and description, referred to as a transmission status in the following) of the transmit end device. For example, the transmit end device is in a transmit state or a non-transmit state. Therefore, the transmit end device and the receive end device may select an air interface transmission technology corresponding to the transmission status, for example, a transmit waveform of an air interface, a frame structure, a retransmission technology, or a code modulation technology, so that the foregoing various air interface transmission technologies can be flexibly used, communication quality is enhanced, and user experience is improved.
However, in this technology, a communications system needs to provide dedicated communication resources and signaling to transmit, between the transmit end device and the receive end device, information that indicates the foregoing transmission statuses, causing interaction between the transmit end device and the receive end device to be complex and communication resource overheads to be increased.